Vapor electric device.



H. F.. PERKINS.

VAPOR ELECTRIC DEVICE.

APPLICATION FuE-'ED APR. 14. 1915."

1,240R'72. l Patentedsgpt. 18,1917.

` Havg Ff Perkins,

HARRY F. PERKINS, 0F SCHENECTADY, NEW YORK, ASSIGNOR TO'GEERAI. ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

VAPOR ELECTRIC envien.

Specification of Letters Patent.

imi-cnice sept. is, 1917.

Application filed April 1.4, 1915. 'Serial No. 21,271.

To all 'whm it may concern B'e it known thatl I, I-laiiny F. Fiamma.

a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York, haver-invented certain new and useful Improvements inVapor Electric Devices, of which `the following` is a`specimercury arc rectifiers.

1n" the operation of electric arc devices containing vapo'rizable material, such as mercury, a conducting material is found to deposit on relatively cool parts of the interior exposed surfaces of the apparatus. This material appears to consist partly of oxidized mercury and partly of impurities but Whatever its nature ,thisdeposit is conductingI and is a source ot' trouble in the ope 'ation of the rectifier. Condensed mercury is also deposited on insulating surfaces es pecially when the device is cold as at start.- ing.

I have found that the cond noting material is deposited in some manner by the vapor blast and `that when i'irojections or barriers on the interior surface ot' thev device extend transversely to the vapor blast that al part of the surface is thereby shielded from the deposit. i

In accordance with my invention insulators within the rectifier are provided with shielding devices. such as ridges or conv'olutions in the recesses of which the conducting material will not be deposited, thus insuring clean bands or zones on the surface of the insulation.

In the aceon'ijninving drawing `Figure. 1 is anA outline vie u ot the vapor device showing the relation ot' the various parts; Fig. 2 is a detail sectional view of one forni of cathode seal einln'idyinginy invention; Fig. El ishk sectional view of another iforin of seal.` y i (')ne forni of vapor electric apparat-us, to which mV invention is particularly applicable. is the metal-walled mercury arc rectifier shown in general outlines in Fig.y l.. The device consists of a main arc chamber 1A containingr main anodes 2,2' surrounded by hoods 3, r3" and a v.starting anode. 4. The

main chamber 1 communicates with a chamber 5 containing the cathode'. The electrode seals have been merely indicated, and for a more complete description of a form of nie,

chaniral seal and other structural 'details suitable i'or a metal-walled evacuated container, reterence may be had to U. S. latent No, 1,118,3S0'to W. E. Story.

A cathode chamber is shown in greater detail in Fig.' 2, the clanij'iiug' devices for holding` together the" parts of the cathode seal beingI omitted, and the bottom plate i' being shown broken away. The lower wall tl ofthe fathode container consists of metal. It is separated from the plate S by a section of insulation 7 and bears against a section 10I of porcelain or other suitable inert, gastight insulation. lVashers ll consisting of aluminum, copper, asbestos or other compressible material are interposed between the insulating section 10 and the adjoining parts 1 and 9 respectively. The. insulating section 10 is provided 0n its inner surface,

asindicated, with a series oic projecting convolutions or ridges l2 substantially parallel to the surface of the body of mercury 13 and interposed in the path of the arc blast' en'ian'ating from the n'iercury cathode 13. I have 'found in practice, when the ,insulating sections are thus provided with outwardly projecting barriers or ridges, that the recess or. hollows between the ridges remain freel from conducting deposit, the ridges casting shadows on theinsulatmg surfaces when subjected to the vaporblast.

In Fig. 3 the entire cathode container 14 consists of insulating material. It is anchored in place by the projecting lugs 15 attached to the sidesy of the outer metal cup 1li ot' the cathode. This 'metal cup 16 is attached to the main bod)T 1 of the vapor device by means of bolts 17 or in any other suitable manner, a washer 1S being interposed to make. a vaeuunrtight seal. Electrical (ainiiection may be made with the.'

cathode 13 through a rod 19 projecting through the side of the cathode chamber anil .having at its end a depending conductor 20 dipping into the mercury. 'lhe terminal lil is surrounded by ai'iiinsulating tube 21. The rods. ,22 which are screwed into the flange Q3 and serve to attiwh-the current con veying terminal to tbe'body of the rectiiier have been merely indicated as this structure is not part of my present inif'ention.

The mercury evaporated froni'tl e cathode 13 and condensed in the upper part of the icc lie

rectifier is returned tothe annular space between the cathode cup 14 `and ythe metal vvall of the cathode container and this nier-4 clury drains back into the cathode cup through a sloping orifice 24. The ridges on the surface of the cathode cup assist in breaking up the mercury stream into drops so as to prevent a short circuit between the cathode and the 'metal wall of the cathode chamber. j i

lVhat I claim as new and desire to secure by Letters Patent of the vUnited Statesrisr l; A vapor electric devicecomprising a metal container, a raporizahle cathode, one or more cooperating anodes, and means for f eleerically insulating the cathode fromrthe mainiipart of the container, said insulatingr means having a plurality of ridges extending` transversely between the cathode and the-anode or anodes'. 4 i

2. A vapor electric device comprising a mercury. cathode, `one or more cooperating anodes and an inclosing envelop, the cathode-containing,r part of said envelop consisting at least in part of insulating.: material, the surface ot' which is provided with' annular protuheranees.

3. ln a vapor are device, amercury cath-l ode and a rontaiuer therefor consistingY in part at least ot porcelain and ha ving a plurality of ridges loraled on the surface of` the eoutaner above the mercury surface and substantially parallel thereto.

.ln witness whereof` I have hereunto set in v hand this 13th dav of April, 1915.

HARRY F. PERKINS. 

